Directions
Place your slow cooker on a stable, heat-resistant surface. If desired, lightly coat the inside with nonstick cooking spray to make cleanup easier.
Spread the sliced onions evenly across the bottom of the slow cooker. This creates a flavorful base and helps prevent the burgers from sticking.
Arrange the frozen beef patties over the onions in a single layer whenever possible. Slight overlapping is acceptable, but avoid stacking them too heavily.
Scatter the mushrooms around and over the patties, filling any open spaces.
Pour the steak sauce evenly over the patties, onions, and mushrooms, making sure all ingredients are coated.
Cover with the lid and cook:
• On Low for 5 to 6 hours
• On High for 3 to 3½ hours
The burgers should reach an internal temperature of at least 160°F (71°C) before serving.
Avoid lifting the lid frequently during cooking, as this releases heat and can extend cooking time.
Once fully cooked, carefully remove the burgers using a spatula. They will be very tender.
Stir the onions and mushrooms into the remaining sauce to create a rich topping.
Toast the buns if desired, place a burger on each bun, and spoon generous amounts of the onion-mushroom mixture over the top.
Tips for Success
Using frozen patties helps the burgers retain moisture during the slow cooking process.
Choose your favorite steak sauce to customize the flavor profile. Different brands can provide sweeter, tangier, or bolder steakhouse flavors.
For extra richness, add a slice of cheese during the final few minutes before serving.
Want to make the recipe even more family-friendly? These easy variations allow you to adapt the burgers to every taste preference.
